Clinico-physio-pathologic studies from the viewpoint of neuromuscular disorders were done in 5 cases of juvenile diabetes mellitus of which ages at the onset of the disease were 13 to 22 years. As regards pathologic studies, the quadriceps muscle and the sural nerve were obtained in each case by means of biopsy. Both conventional histologic and electron microscopic observations were performed.The results obtained were summarized as follows.1) These 5 cases showed some abnormalities in all the examinations performed including clinical neurologic examinations, electromyographic studies, examinations of motor nerve conduction velocities, and morphologic observations of the muscle and the nerve.2) As for neurologic signs, autonomic symptoms were noted without exception, while neither hyporeflexia nor disturbed vibratory sensation which was the main neurological symptom in adult type of diabetes mellitus, was frequently observed.3) Electromyographically, the result was mixed patterns of neurogenic and myogenic tendencies as the authors had pointed out on the adult type of diabetes mellitus. However there were more myogenic tendencies in the juvenile type than in the adult type.4) The morphological changes of either the muscle or the nerve were not exactly parallel with the degree of clinical neurological symptoms, though histologic changes were the most remarkable in the case which showed the severest neurological signs of the 5 cases.5) Principal histologic observations on the quadriceps femoris were individual muscle fibre atrophy, focal degeneration of muscle fibres, hypertrophic or degenerative muscle fibres, central nuclei and marked variations in the diameter of fibres. Pictures of grouping small fibres were noted in 2 out of 5 cases.6) Electron microscopically the changes in the muscle consisted of thickening of the basement membrane of the interstitial capillary, increase of interfibrillar glycogen granules, degeneration of myofibrils sometimes with complete loss of the normal architecture, vacuole formation between myofibrils and thickening of the limiting membrane of the muscle fibre. Abnormal increase of subsarcolemmal lipopigment, one of the most prominent findings in the adult diabetes, was not markedly observed.7) No relation between the morphological changes and duration of the disease was noted. Nevertheless, endoneural fibrosis in the sural nerve seemed to be more prominent in the cases of longer durations. It was noteworthy that the case 3 and the case 4, of which the durations of the disease were a few months, showed extensive morphological changes as shown in the table 3 and the table 4.8) From morphological studies, the authors assumed that in juvenile diabetes mellitus changes of the axon might precede those of the myelin, and vice versa in the adult type.

The relation of insulin-degrading enzyme to the cause of discrepancy of insulin activities between immunological and biological determinations was studied.For the purpose of determination of insulin degradation, a separation with a thin-layer chromatograph and qualitative and quantitative determinations with a chromatoscannogram of degradation products derived from 131I-labeled insulin by muscle tissue were performed.Under the conditions of the measurement of insulin-like activity (ILA) using a hemidiaphragm, the accumulative residual percentage of 131I-labeled insulin (250μU) was calculated as 42.2 % of the initial insulin concentration in Krebs-Ringer bicarbonate buffer solution at 37°C for 120 minutes, while the accumulative residual percentage of the same dose of 1311-labeled insulin added to normal human serumbuffer solution was calculated as 85.6 %. The fact indicates that ILA in serum is expressed as an approximately two fold concentration by calculations using the insulin standard curve. This could be one of the causes of the discrepancy of insulin activities between IRI and ILA in seum.The addition of the degradation product of insulin induced by means of muscle tissue to the mixture of insulin and hemidiaphragm in vitro inhibited the insulin degrading enzyme activity and also reduced to some extent the biological effect of insulin on the diaphragm. This suggests that the degradation product is competitive with insulin probably against the membrane of muscle cells.

Polyaminostyrene, and diazopolystyrene quenched with β-naphthol bound insulin in a manner of physical adsorption (polyaminostyrene-insulin, PAS-I and β-naphthyl-azo-polystyrene-insulin, β-NAS-I, respectively). The properties of these physically modified insulin preparations were compared with that of polystyrene-azo-insulin (PAI), in which insulin was coupled chemically by azo linkages, and following results were obtained:1). The insulin content of these preparations was found to be 50 to 70 mg/g of PAS-I, 80 to 100 mg/g of β-NAS-I and 130 to 170 mg/g of PAI. The biological activities of PAS-I, β-NAS-I and PAI were about 70, 40 and 40% of the original value, respectively.2). By a successive washing with mild acid, insulin was unbound from its physical binding to polyaminostyrene (PAS-I). The biological activity of β-NAS-I was reduced to 10 to 20% of the original value after liberating about one forth of insulin by mild acid treatment.3). By acrylamide-gel electrophoresis, free insulin was detected in the PAI preparation. PAI without any demonstrable free insulin by a successive washing procedure lost its biological activity as well as immunoreactivity, even though a considerable amount of insulin was still found in PAI preparation.4). PAS-I was destroyed, to some extent, by digestive enzymes.β-NAS-I and PAI, on the other hand, were quite resistent to peptic and α-chymotryptic digestions in vitro.From these results, the properties of insulin fixed physically on β-naphthyl-azo-polystyrene were found to be almost similar to those of chemically coupled by azo linkages. These findings also suggest that insulin fixed tightly (either chemically or physically) plays no significant role in its pharmacodynamic action. Insulin fixed loosely appears to be of importance for its activity.

Insulin was bound physically to DEAE-cellulose, AE-cellulose, activated carbon and aluminium silicate. The biological and immunological activities of these preparations were compared with that of standard insulin. The hydrolyses of these preparations with pepsin and α-chymotrypsin were also measured in vitro, and following results were obtained:1). The insulin content of these preparations was increased in the following order; aluminium silicateinsulin, activated carbon-insulin, AE-cellulose-insulin and DEAE-cellulose-insulin.2). By a successive washing procedure, insulin was shown to be fixed tightly on aluminium silicate, and loosely on AE-cellulose and activated carbon. Under the condition of pH 8.0, DEAE-cellulose bound insulin tightly.3). The biological activity of these preparations was found to be between 50 to 70% of the original value. As compared with the biological activity, a slightly less immunoreactivity was recovered.4). DEAE-cellulose-insulin was readily destroyed by pepsin, but relatively resistant to a-chymotrypsin. A relative resistance to peptic digestion was found in AE-cellulose-insulin. Aluminium silicate-insulin was resistant to peptic digestion. Activated carbon-insulin was quite resistant to the action of both peptic and α-chymotryptic digestions.From these results, it is indicated that these modified insulin preparations which are not affected by peptic and α-chymotryptic digestions, might be used as a tool for studying on the enteral administration of insulin.

Dextrostix, containing glucose oxidase, is a rapid quantitative enzyme-strip method of blood sugar, but for colour matching with the naked eye the previous simple method was not enough to know the exact levels of blood sugar.Recently a Reflectance Meter has been introduced to determine photoelectrically the final colour of the strip reacted with blood sugar are follows;1) Blood sugar levels are well corelated between in Dextrostix Reflectance Meter system and inautoanalyzer (r≥0.87).2) Results are well reproducible.3) The reation of Dextro stix with blood sugar is affected within limited range is permitted in clinical purpose.

Several factors which stimulate the secretion of pancreatic glucagon have been reported by many authors based on the results mostly obtained in animal experiments. Since amino acids mixture is one of the most potent stimulators for glucagon secretion from the pancreas, the plasma response to arginine infusion in man was compared with those to other various stimuli.Plasma glucagon was determined by the radioimmunoassay using an anti-glucagon serum, which is relatively specific for pancreatic glucagon but still cross-reacts with enteroglucagon.The plasma glucagon level rose after the infusion of arginine for 30 minutes in amount of 300 ml of 10 per cent solution in normal subjects as well as in diabetic patients. Arginine infusion caused a rise in plasma glucagon in patients with hypoglycemia or other endocrine diseases. Whereas insulin induced hypoglycemia stimulates glucagon secretion in normal subjects, it did not cause any rise in plasma glucagon in diabetic patients. A rapid fall of blood glucose, cataglycemia, did not produce any change in the level of plasma glucagon. Plasma insulin rose after the injection of the tetrapeptide of human gastrin or secretin but the plasma glucagon response to these hormones was not observed at all. Pancreozymin, which is known as one of the most potent stimulators for the pancreatic secretion of glucagon or insulin in dogs, did not produce any rise in plasma glucagon nor insulin.In comparison with the plasma response of glucagon to several stimuli, it is proved that only arginine infusion or insulin-induced hypoglycemia could produce an increase in plasma glucagon in the peripheral vein in normal subjects. In diabetic patients, however, insulin-induced hypoglycemia did not produce a marked increase in plasma insulin. Furthermore, it is dangerous to perform insulin test in patients with hypoglycemia. Therefore, our results suggest that arginine infusion test is the most useful among the several factors, which stimulate glucagon secretion from the pancreas in man.

Two cases of children with maturity-onset type diabetes in the siblings of a 14 year-old boy and a 11 year-old girl were reported.Their mother and maternal grandmother had been diabetic, but there was no history of diabetes on the paternal side.They were tested and followed by oral glucose tolerance test every three months, and the blood sugar values and plasma insulin responses to glucose were observed.The glucose intolerance became worse progressively, showing a slight fluctuation and finally developed into overt diabetes during the period of five and a half years.A significant but delayed plasma insulin response was seen during the state of mild carbohydrate intolerance, but low insulin response was found during the state of severe carbohydrate intolerance. However, they responded to sulfonylureas.They were the cases of maturity-onset type seen in the childhood.

Induced hyperglycemia during hemodialysis with standard dextrose solution is unfavorable in diabetic patients with chronic renal failure.In this study, the solution containing xylitol instead of dextrose for hemodialysis was applied to avoid hyperglycemia. The effect of xylitol or dextrose solution in hemodialysis was comapred in two Kimmelstiel-Wilson's syndrome with anasarca. No marked increase of blood glucose level following hemodialysis with xylitol solution was noted. Anasarca was relieved dramatically after hemodialysis with xylitol as well as dextrose, and treated succesfully for long term. Depletion of serum potassium and reduction of serum urea-N and creatinine were observed either with glucoseor xylitol solution.

The effect of tolbutamide on the oxidation and phosphorylation of the isolated rat liver mitochondria was tested, and following results were obtained.1. More than 30 mg% tolbutamide increased the state 4 respiration rate and decreased respiratory control of isolated rat liver mitochondria.2. More than 80 mg% tolbutamide decreased the state 3 respiration rate.3. 100 mg% tolbutamide decreased P/o ratio to zero.4. 100 mg% tolbutamide increased apparently rutamycin sensitive ATP-ase activity of rat liver mitochondria.Above mentioned results showed that tolbutamide was one of uncouplers. This results were discussed in relation to the side effect of tolbutamide.